If anybody finds this usefull:

I had a problem with one of my customers, where paradox aplication was
freezing constantly (5 times a day, every user).

Paradox applicatin just froze and was nonresponsive.
Only option ctrl+alt+del.
And this happened after some time of inactivity AND also during notmal work.

Firs thought was "bad switch".
New switch did not help.

next: "net config server /autodisconnect:-1"
(disable autodisconect of network drives)
Did not help.

Next: "bad network card on server". New card did not help.

Next: "new temporary server". Did not help.

To make the long story short:

Problem was in combination of win10 / server 2008 / Group policy
Their network was a domain network.
Their administrator di network mapping with Group Policy.
And behaviour of mapped drives in GP changed with Win8.
Group policy is processed every couple of hours and in that process mapped 
drives were
disconected and reconected. Instead of just checked, as it was the case 
prior to Win 8.

Solution was to make group policy just "Update"  network drives, instead of 
"Replacin" it.

https://www.mcbsys.com/blog/2016/08/windows-10-repeatedly-disconnects-network-drives/

Jure